Argument assertions

Arguments.java

public class Arguments {

  // ------------------------------------------------------------
  // Checks

  public static <T> T require(T argument, Predicate<T> condition, Supplier<String> msgSupplier) {
    return require(argument, () -> condition.test(argument), msgSupplier);
  }

  public static <T> T requireNot(T argument, Predicate<T> condition, Supplier<String> msgSupplier) {
    return require(argument, condition.negate(), msgSupplier);
  }

  public static <T> T require(T argument, BooleanSupplier test, Supplier<String> msgSupplier) {
    if (test.getAsBoolean()) {
      return argument;
    }
    throw new IllegalArgumentException(msgSupplier.get());
  }

  public static <T> T requireNot(T argument, BooleanSupplier test, Supplier<String> msgSupplier) {
    return require(argument, () -> !test.getAsBoolean(), msgSupplier);
  }

  // ------------------------------------------------------------
  // Constructor

  private Arguments() {
    // private to prevent accidental instatiation
  }
}